(1) Field of the Invention
The present invention relates generally to active sonar countermeasures. More particularly, this invention relates to a cost effective, cylindrically shaped acoustic countermeasure that lowers transmitted frequencies by one half as compared to contemporary transducers of the same size.
(2) Description of the Prior Art
Acoustic countermeasures are an integral part of undersea offensive and defensive operations, and compact transducers are routinely used as expendable acoustic sources. The expendable sources can project acoustic energy over bandwidths that are predetermined or limited by the dimensions of a source's cylindrical-shaped housing. The current state of the art expendable acoustic source is only capable of projecting acoustic energy at a low end frequency level that is approximately two times higher than the desired or optimum low frequency for successful countermeasure operations.
The size of a source's housing and hence the lowest operating frequencies are constrained by the dimensions of the launch or deployment systems in the submerged or surface vessel. Larger acoustic countermeasures would be capable of lower frequency operation, but larger sound sources are incompatible with existing systems used to deploy expendable acoustic countermeasures.
Thus, in accordance with this inventive concept, a need has been recognized in the state of the art for an expendable cylindrical-shaped acoustic source that is capable of operating at one half the present lowest operating frequency of a contemporary source of similar dimensions.